The present invention relates to a process for the production of polyethylene and more particularly to an efficient process for the production of polyethylene having a broad distribution of molecular weight by the use of a specific catalyst.
Polyethylene has been widely used as an excellent synthetic resin in various applications and in particular, polyethylene having a broad distribution of molecular weight has been desired in view of moldability, physical properties of molded article, etc.
It is known that polyethylene for the production of a catalyst prepared by reacting a magnesium compound and a titanium halide has a higher activity than the so-called Ziegler catalyst polyethylene. In accordance with the conventional methods of production, if the distribution range of molecular weight of the product polyethylene is sufficiently broad, the catalyst activity will be low. These conventional methods are disadvantageous in that the production efficiency is low and since a large amount of catalyst is required, it is necessary to provide an operation for removal of the catalyst from the polyethylene products.
An object of the invention is to provide an efficient process for the production of polyethylene having a broad distribution of molecular weight by the use of a catalyst having high activity.
Another object of the invention is to provide a process for the production of polyethylene which does not require a de-ash step (i.e., a step of removing the catalyst).
A further object of the invention is to provide a process for the production of polyethylene having a large apparent density, a relatively uniform particle size, and a very low content of fine powder.